Removable data storage cartridges typically include some mechanism to protect the data storage media when the cartridges are not in use. Typically those protective mechanisms are referred to as shutters. Many of the shutters expose openings in the data storage cartridges by moving translationally, i.e., in a straight line. One example of such a shutter is provided in connection with micro-floppy diskettes that include circular magnetic data storage media having a diameter of 3" inches (8.9 cm).
Shutters that rotate to expose a portion of the media can be useful to decrease the size of the data storage cartridge because the shutter and cartridge can more closely follow the contours of the circular media while also allowing the head actuator mechanism to position itself over the data recording area of the disk.
Other shutters rotate about a portion of the data storage cartridge to expose the media contained within the cartridge. One example of such a cartridge and shutter design is disclosed in U.S. Pat. No. 5,636,095 (McGrath et al.). The shutter 50 encloses a circular segment of the media. One disadvantage of the design of the cartridge and rotary shutter of McGrath et al. lies in the relatively large number of parts required to effect the design. Furthermore, assembly of the cartridge is difficult process. As a result, the cost of manufacturing the data storage cartridges is increased. In addition, the media itself cannot typically be tested until the entire cartridge is assembled, thereby increasing waste if the media does not meet the required performance standards.
Cost of manufacturing is an important consideration in the design of many data storage cartridges. Any benefit in terms of reduced manufacturing costs can be extremely important for data storage cartridges.
Another consideration in the design of data storage cartridges is the size of the cartridge relative to the size of the media. It is preferred that the cartridges maximize the portion of their volume occupied by the data storage media and reduce the portion of the volume devoted to the other components of the cartridge. Space utilization is an increasing concern as the size of devices using data storage cartridges continues to decrease.